Field of the Invention
The present invention is directed generally to systems and methods for shaping tubing, and more specifically, to systems and methods for end forming tubes for use in systems such as vehicle exhaust systems or other systems that utilize tubes.
Description of the Related Art
Tube end forming is required for many tubing applications. Generally, tube end forms are utilized to provide some type of connection to another tube, hose, block, etc. There are several types of forms that can be applied to the end of a tube. These types include reduction, expansion, flare, bead, impact (or thickening), and the like. One popular process for end forming is referred to as “ram-type end forming.” Ram-type end forming is a cold working process by which a tube to be formed is held securely in a set of clamp blocks. Forming is accomplished when one or more end forming tools (e.g., punches) positioned in alignment with the target end of the tube are “rammed” or pressed over the tube end. In addition to or as an alternative to an axial force being applied to the target end, expansion punches may be used to provide a radial force to an internal or external surface of the tube.
To facilitate the movement of the forming tools and/or clamp blocks, end forming machines typically include one or more mechanical actuators. In some machines, hydraulic cylinders are used as the actuators. Traditional hydraulic systems for end forming machines utilize an alternating current (AC) motor driving a hydraulic pump such that hydraulic pressure is constantly available to the system. The actual flow of oil to the moving parts of the machine is normally controlled using solenoid-operated valves to direct the flow of oil according to the required machine cycle. Even when the machine is not in motion and no oil pressure and/or flow is required, the AC motor continuously drives the hydraulic pump. As can be appreciated, constant noise, heat, and energy usage are all associated with end forming machines that use traditional hydraulic power units.